摘要
首先通过电聚合方法在玻碳电极表面制备了聚(3-甲基噻吩)(P3MT)修饰膜,然后在一定电位下将DNA分子电沉积到P3MT表面,制备了DNA/(P3MT)复合膜修饰玻碳电极.研究了8-羟基-2'-脱氧鸟嘌呤核苷(8-OH-dG)在该复合膜修饰电极上的伏安行为以及扫描速度、pH值和尿酸对其伏安行为和检测的影响.实验结果表明,该复合膜修饰电极结合了P3MT和DNA两者的优点,使8-OH-dG在复合膜修饰电极上的电化学行为明显改善,而且具有很好的重现性和稳定性.在0.1mol/LpH7.0的磷酸盐缓冲溶液(PBS)中,8-OH-dG的氧化峰电流与其浓度在0.28～4.2μmol/L和4.2～19.6μmol/L两个范围内成良好的线性关系,检出限为56nmol/L(S/N=3).该研究可以为制备HPLC或毛细管电泳电化学检测器检测8-OH-dG打下一定的基础,因此在检测尿样中8-OH-dG的研究方面具有潜在的应用价值.
A composite film of DNA/poly（3-methylthiophene） （P3MT） modified glassy carbon electrode （GCE） was fabricated by electro-deposition method. P3MT film was firstly electropolymerized at the GCE and the DNA layer was then immobilized on the P3MT layer by electrochemical method. The voltammetric behavior of 8-hydroxy-2＇- deoxyguanosine （8-OH-dG） at the composite film modified electrode was studied. The effects of scan rates, pH and the interference of uric acid （UA） on the voltammetric behavior and detection of 8-OH-dG were also discussed. The experimental results suggest that the electrochemical behavior of 8-OH-dG at the composite film modified electrode was greatly improved due to the combination of the advantages of P3MT and DNA. In 0.1 mol/L pH 7.0 phosphate buffer solution （PBS）, the anodic peak currents of 8-OH-dG were linear with the 8-OH-dG concentration in two in- tervals, viz. 0.28 - 4.2 μmol/L and 4.2 - 19.6μmol/L, respectively. The detection limit of 56 nmol/L 8-OH-dG could be estimated （S/N=3）. This proposed composite film modified electrode also shows excellent reproducibility and stability. This composite film modified electrode may have the potential application for the detection of 8-OH-dG in human urine.
出处
《中国科学（B辑）》
CSCD
北大核心
2009年第11期1536-1543,共8页
Science in China(Series B)
基金
国家自然科学基金(批准号:20475024,20775031)
山东省“泰山学者”建设工程专项经费资助
